Mekbib Destaw B, McDonough Ian M
Department of Psychology, Binghamton University, Binghamton, New York, 13902, USA.
Center for Cognitive Applications, Binghamton University, Binghamton, New York, 13902, USA.
Ann Clin Transl Neurol. 2025 Feb;12(2):246-254. doi: 10.1002/acn3.52290. Epub 2025 Jan 7.
Episodic memory is a critical cognitive function that enables the encoding, storage, and retrieval of new information. Memory consolidation, a key stage of episodic memory, stabilizes this newly encoded information into long-lasting brain "storage." Studies using fMRI to investigate post-encoding awake rest holds promise to shed light on early, immediate consolidation mechanisms. Here, we review fMRI studies during episodic memory to document common methods to investigate post-encoding consolidation, such as multivoxel pattern analysis (MVPA) and functional connectivity, and the current state of the science in both healthy younger and older adults. In young adults, post-encoding reactivation of stimuli-specific neural patterns in the hippocampus and its connectivity with cortical and subcortical areas (e.g., visual-temporal cortex, medial prefrontal, and medial parietal cortex) correlate with subsequent memory performance. Conversely, studies in older adults highlight the importance of large-scale brain networks during post-encoding rest, particularly the default mode network (DMN). Alterations in connectivity between the DMN and task-positive networks may help older adults maintain episodic memory. Furthermore, non-invasive brain stimulation techniques can enhance these post-encoding consolidation processes and improve memory performance in both younger and older adults. Notably, a lack of studies has investigated post-encoding memory consolidation in neurodegenerative disorders. This review underscores the importance of understanding how post-encoding neural reactivation and connectivity evolve with age to partially explain age-related declines in episodic memory performance and how such declines can be restored.
情景记忆是一种关键的认知功能，它能够对新信息进行编码、存储和检索。记忆巩固是情景记忆的一个关键阶段，它将新编码的信息稳定到持久的大脑“存储”中。利用功能磁共振成像（fMRI）研究编码后清醒休息状态有望揭示早期的即时巩固机制。在这里，我们回顾了情景记忆期间的fMRI研究，以记录研究编码后巩固的常用方法，如多体素模式分析（MVPA）和功能连接性，以及健康年轻人和老年人的当前科学现状。在年轻人中，海马体中刺激特异性神经模式的编码后再激活及其与皮质和皮质下区域（如视觉颞叶皮质、内侧前额叶皮质和内侧顶叶皮质）的连接性与随后的记忆表现相关。相反，对老年人的研究强调了编码后休息期间大规模脑网络的重要性，特别是默认模式网络（DMN）。DMN与任务阳性网络之间连接性的改变可能有助于老年人维持情景记忆。此外，非侵入性脑刺激技术可以增强这些编码后巩固过程，并改善年轻人和老年人的记忆表现。值得注意的是，缺乏研究调查神经退行性疾病中编码后的记忆巩固。这篇综述强调了理解编码后神经再激活和连接性如何随年龄演变，以部分解释情景记忆表现中与年龄相关的下降，以及如何恢复这种下降的重要性。
